Amazon [amazon.com] has Belkin 20W USB-C Foldable Wall Charger for $6.49. Shipping is free w/ Prime or on $35+.
Best Buy [bestbuy.com] also has Belkin 20W USB-C Foldable Wall Charger for $6.49. Shipping is free for My Best Buy members (free to join [bestbuy.com]). Otherwise, select free store pickup where available.